EUVD-2024-0254

Comprehensive Technical Analysis of EUVD-2024-0254

1. Vulnerability Assessment and Severity Evaluation

Vulnerability Description: The vulnerability in BuildKit allows a malicious BuildKit frontend or Dockerfile using the RUN --mount feature to trick the system into removing a file outside the container, from the host system. This issue arises from the improper handling of empty files created for mountpoints.

Severity Evaluation: The vulnerability has a CVSS Base Score of 10.0, which is the highest possible score, indicating a critical severity. The CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:H breaks down as follows:

• Attack Vector (AV): Network (N) - The vulnerability can be exploited remotely over the network.
• Attack Complexity (AC): Low (L) - The attack requires minimal complexity.
• Privileges Required (PR): None (N) - No special privileges are required to exploit the vulnerability.
• User Interaction (UI): None (N) - No user interaction is required.
• Scope (S): Changed (C) - The vulnerability affects a different security scope.
• Confidentiality (C): None (N) - There is no impact on confidentiality.
• Integrity (I): High (H) - There is a high impact on integrity.
• Availability (A): High (H) - There is a high impact on availability.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Malicious BuildKit Frontend: An attacker could create a malicious BuildKit frontend that exploits the vulnerability.
• Untrusted Dockerfile: An attacker could craft a Dockerfile with a RUN --mount command designed to remove critical files from the host system.

Exploitation Methods:

• Remote Exploitation: An attacker could remotely exploit the vulnerability by injecting a malicious Dockerfile into a build process.
• Supply Chain Attack: An attacker could compromise a build pipeline by introducing a malicious BuildKit frontend or Dockerfile.

3. Affected Systems and Software Versions

Affected Software:

• BuildKit versions prior to v0.12.5.

Affected Systems:

• Systems running BuildKit for building Docker images.
• Systems that use BuildKit frontends from untrusted sources.
• Systems that build Dockerfiles containing the RUN --mount feature.

4. Recommended Mitigation Strategies

Immediate Mitigation:

• Upgrade BuildKit: Upgrade to BuildKit version v0.12.5 or later, which includes the fix for this vulnerability.
• Avoid Untrusted Sources: Ensure that BuildKit frontends and Dockerfiles come from trusted sources.
• Monitor Build Processes: Implement monitoring and logging for build processes to detect any suspicious activities.

Long-Term Mitigation:

• Security Audits: Conduct regular security audits of build pipelines and Dockerfiles.
• Access Controls: Implement strict access controls for build systems and ensure that only authorized users can modify build configurations.
• Patch Management: Establish a robust patch management process to ensure timely updates of all software components.

5. Impact on European Cybersecurity Landscape

Critical Infrastructure:

• The vulnerability poses a significant risk to critical infrastructure that relies on containerized applications built using BuildKit.
• Organizations in sectors such as finance, healthcare, and government services could be particularly affected.

Supply Chain Security:

• The vulnerability highlights the importance of supply chain security, as compromised build processes can introduce vulnerabilities into software products.
• European organizations need to enhance their supply chain security measures to mitigate such risks.

Regulatory Compliance:

• Organizations must ensure compliance with European cybersecurity regulations, such as the NIS Directive and GDPR, which emphasize the importance of securing critical infrastructure and protecting personal data.

6. Technical Details for Security Professionals

Technical Analysis:

• The vulnerability stems from the improper handling of empty files created for mountpoints, allowing an attacker to manipulate the system into removing files from the host.
• The RUN --mount feature in Dockerfiles is particularly susceptible to this exploit.

Detection and Response:

• Detection: Implement intrusion detection systems (IDS) and intrusion prevention systems (IPS) to monitor for suspicious build activities.
• Response: Develop an incident response plan that includes steps for identifying, containing, and remediating the vulnerability.

Forensic Analysis:

• Conduct forensic analysis of build logs and system logs to identify any unauthorized file deletions or modifications.
• Use forensic tools to trace the source of malicious Dockerfiles or BuildKit frontends.

Conclusion: The vulnerability in BuildKit (EUVD-2024-0254) is critical and requires immediate attention from cybersecurity professionals. Organizations should prioritize upgrading to the patched version of BuildKit and implement robust security measures to protect their build processes and supply chains. The European cybersecurity landscape must adapt to such threats by enhancing regulatory compliance and adopting best practices for securing critical infrastructure.